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GLOBAL EXISTENCE,UNIQUENESS,AND STABILITY FOR A NONLINEAR HYPERBOLIC-PARABOLIC PROBLEM IN PULSE COMBUSTION

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Acta Mathematica Scientia 2012年第1期32卷 41-74页

作者： olga Terlyga Hamid Bellout Frederick Bloom Fermi National Laboratory Department of Mathematical Sciences Northern Illinois University

A global existence theorem is established for an initial-boundary value prob- lem, with time-dependent boundary data, arising in a lumped parameter model of pulse combustion; the model in question gives rise to a nonlinear mixed hyperbolic-parabolic sys- tem. Using results previously established for the associated linear problem, a fixed point argument is employed to prove local existence for a regularized version of the nonlinear problem with artificial viscosity. Appropriate a-priori estimates are then derived which imply that the local existence result can be extended to a global existence theorem for the regularized problem. Finally, a different set of a priori estimates is generated which allows for taking the limit as the artificial viscosity parameter converges to zero; the corresponding solution of the regularized problem is then proven to converge to the unique solution of the initial-boundary value problem for the original, nonlinear, hyperbolic-parabolic system.

关键词： pulse combustion hyperbolic-parabolic system global existence regularity

Influence of polyolefin fibers on the strength and deformability properties of road pavement concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 407-417页

作者： olga Smirnova Alexey Kharitonov Yuriy Belentsov Department of Constructing Mining Enterprises and Underground Structures Saint-Petersburg Mining UniversitySaint Petersburg 199106Russia Department of Technology of Building Materials and Metrology Saint-Petersburg State University of Architecture and Civil EngineeringSaint Petersburg 190005Russia Department of Building Materials and Technologies Emperor Alexander I St.Petersburg State Transport UniversitySaint Petersburg 190031Russia

Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the *** ways of fibers introduction into fresh concrete were investigated. It was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m^3 was 23% and 29%;for macrofibers in quantity of 3 kg/m^3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete.

关键词： Road pavement concrete Polyolefin fibers Strength Elastic modulus Abrasion Water-to-cement ratio

Control of chaotic oscillations of a satellite

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Applied Mathematics and Mechanics(English Edition) 2007年第7期28卷 893-900页

作者： Alexey Bobtsov Nikolay Nikolaev olga Slita Department of Control Systems and Informatics Saint-Petersburg State University of Information Technologies Mechanics and OpticsKronverksky Ave.49Saint-Petersburg197101Russia

Analytical conditions and practical methods of their realization are proposed to solve a problem of a command signal tracking for a nonlinear disturbed system. Nonlinear disturbed plants consisting of linear dynamic block and nonlinear block in feedback are considered. Nonlinear part of the plant and disturbance are unknown and bounded. The paper illustrates a possibility of applications of proposed algorithms to control libration angle of satellite.

关键词： adaptive control chaotic behaviour satellite control nonlinear stabilization nonlinear control output control

K^(+) channel-mediated retarded maturation of interneurons and its role in neurodevelopmental disorders

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Neural Regeneration Research 2024年第7期19卷 1403-1404页

作者： Kaizhen Li Daria Savitska olga Garaschuk Laboratory of Systems Neuroscience Department of PhysiologyUniversity of BernBernSwitzerland Institute of Physiology Department of NeurophysiologyEberhard Karls University of TübingenTübingenGermany

De novo mutations in genes encoding K^(+)channels are implicated in many severe neurodevelopmental ***,mutations in KCNA2,encoding the Shaker-type voltage-gated K^(+)channel Kv1.2,and KCNJ2,encoding the inwardly rectifying K^(+)channel Kir2.1,associate with focal and generalized epilepsies,brain atrophy,autism,ataxia and hereditary spastic paraplegia(Syrbe et al.,2015;Masnada et al.,2017;Cheng et al.,2021).

关键词： disorders atrophy

The Influence of Poly(Vinyl Alcohol)on Oil Release Behavior of Polylactide-Based Composites Filled with Linseed Cake

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Journal of Renewable Materials 2020年第4期8卷 347-363页

作者： olga Mysiukiewicz Mateusz Barczewski Joanna Szulc Division of Polymer Processing Institute of Material TechnologyPoznan University of TechnologyPoznan61-138Poland Departament of Food Industry Technology and Engineering Faculty of Chemical Technology and EngineeringUTP University of Science and TechnologyBydgoszcz85-326Poland

In order to limit the negative impact of industry on natural environment,ecological alternatives to conventional polymers are being *** of the most popular“green”polymers is polylactide,which can also be successfully applied as a matrix of *** application of ground linseed cake as a filler for polylactide-based composites is in line with the idea of Circular Economy,and moreover it provides a modifying effect on the polymer by increasing its crystallinity and reducing its *** effect is caused by the presence of linseed oil which can be released to the polymeric matrix in a non-controlled *** order to control the miscibility of the oil and the polymer,we modified the filler particles with poly(vinyl alcohol)before introducing it to the *** concluded that poly(vinyl alcohol),which does not mix with oil,encapsulated the active ingredients inside the filler *** evaluated the mechanical properties of the composites containing 5,10,20 and 30 wt%of the filler in a static tensile stress and by means of dynamic mechanical thermal *** and thermal properties were tested using differential scanning calorimetry as well as thermogravimetric ***’microstructure was evaluated by Scanning Electron *** was found that modifying the oil-rich filler with poly(vinyl alcohol)helps to reduce its release to the matrix and thus limits the plasticizing effect of linseed *** result was in accordance with our hypothesis.

关键词： Polylactide poly(vinyl alcohol) waste filler oil release

Quantum Yang-Baxter equation and constant R-matrix over Grassmann algebra

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第10期6卷 1065-1079页

作者： DUPLIJ Steven KOTULSKA olga SADOVNIKOV Alexander Department of Physics and Technology V.N. Karazin Kharkov National University Svoboda Sq. 4 Kharkov 61077 UkraineDepartment of Physics and Technology V.N. Karazin Kharkov National University Svoboda Sq. 4 Kharkov 61077 UkraineDepartment of Physics and Technology V.N. Karazin Kharkov National University Svoboda Sq. 4 Kharkov 61077 Ukraine

Constant solutions to Yang-Baxter equation are investigated over Grassmann algebra for the case of 6-vertex R-matrix. The general classification of all possible solutions over Grassmann algebra and particular cases with 2,3,4 generators are studied. As distinct from the standard case, when R-matrix over number field can have a maximum 5 nonvanishing elements, we obtain over Grassmann algebra a set of new full 6-vertex solutions. The solutions leading to regular R-matrices which appear in weak Hopf algebras are considered.

关键词： Constant solution Grassmann algebra Regularity R-matrix

Performance of low temperature Microbial Fuel Cells(MFCs)catalyzed by mixed bacterial consortia

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Journal of Environmental Sciences 2017年第2期29卷 284-292页

作者： olga Tkach Thangavel Sangeetha Spiridonova Maria Aijie Wang State Key Laboratory of Urban Water Resources and Enuironment(SKLUWRE) Harbin Institute of TechnologyHarbin 150090China. Key Laboratory of Environmental Biotechnology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Krasnoyarsk State Institution of Railway Vehicles Krasnoyarsk 660028Russia

Microbial Fuel Cells（MFCs） are a promising technology for treating wastewater in a sustainable manner. In potential applications, low temperatures substantially reduce MFC performance. To better understand the effect of temperature and particularly how bioanodes respond to changes in temperature, we investigated the current generation of mixed-culture and pure-culture MFCs at two low temperatures, 10°C and 5°C. The results implied that the mixed-culture MFC sustainably performed better than the pure-culture（Shewanella） MFC at 10°C, but the electrogenic activity of anodic bacteria was substantially reduced at the lower temperature of 5°C. At 10°C, the maximum output voltage generated with the mixed-culture was 540–560 m V, which was 10%–15% higher than that of Shewanella MFCs. The maximum power density reached 465.3 ± 5.8 m W/m^2 for the mixed-culture at10°C, while only 68.7 ± 3.7 m W/m^2 was achieved with the pure-culture. It was shown that the anodic biofilm of the mixed-culture MFC had a lower overpotential and resistance than the pure-culture MFC. Phylogenetic analysis disclosed the prevalence of Geobacter and Pseudomonas rather than Shewanella in the mixed-culture anodic biofilm, which mitigated the increase of resistance or overpotential at low temperatures.

关键词： Microbial fuel cell Psychrophilic bacteria Shewanella Low temperature Bioelectrochemical

The effect of space weather on the ionosphere at the 110°meridian during CAWSES-Ⅱperiod

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Geodesy and Geodynamics 2021年第2期12卷 93-101页

作者： olga Maltseva Tatyana Nikitenko Institute for Physics Southern Federal University344090Rostov-on-DonStachky190Russia

Space weather determines the state of the ionosphere,which is especially important to know during *** study this state,the period of March 7-17,2012,which was recommended by SCOSTEP for detailed studies and called CAWSES-II,was *** this period,the behavior of parameters of the solar wind(SW)and the interplanetary magnetic field(IMF)show a number of *** this paper,we study their relationship with the total electron content(TEC)and the critical frequency(foF2)of the ionosphere at the 110°meridian,near which several ionosondes are located,in the range of 20°N-62.5°*** correlation coefficients of TEC and foF2 with the SW and IMF parameters for the month and the selected period are *** ionosphere showed the considered disturbances in different ways in different latitudinal zones:negative anomalies are observed at high latitudes,and positive ones at low latitudes.A distinctive feature is the presence of signs of a super-fountain *** of TEC and foF2 from their medians can be *** IRI model reacted in the latitude range 40°N-62.5°N in the form of negative anomalies,although positive anomalies were observed in the *** lower latitudes,no reaction was *** all factors(F10.7,Dst,Kp,IMF,Np),three zones(high-latitude,midlatitude,and low-latitude)are distinguished for different *** strongest influence of disturbances on the correlation coefficients is observed in the zone of 37.5°N 62.5°N.

关键词： Ionosphere Space weather Total electron content Correlation

Visible light driven mineralization of spiramycin over photostructured N-doped TiO2 on up conversion phosphors

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Journal of Environmental Sciences 2017年第4期29卷 268-276页

作者： olga Sacco Vincenzo Vaiano Diana Sannino Paolo Ciambelli University of Salerno Department of Industrial Engineering

A novel visible light-active photocatalyst formulation（NdT/OP） was obtained by supporting N-doped TiO2（NdT） particles on up-conversion luminescent organic phosphors（OP）. The photocatalytic activity of such catalysts was evaluated for the mineralization process of spiramycin in aqueous solution. The effect of NdT loading in the range 15–60 wt.% on bulk and surface characteristics of NdT/OP catalysts was investigated by several chemicophysical characterization techniques. The photocatalytic performance of NdT/OP catalysts in the removal of spyramicin from aqueous solution was assessed through photocatalytic tests under visible light irradiation. Total organic carbon（TOC） of aqueous solution,and CO and CO2 gas concentrations evolved during the photodegradation were analyzed. A dramatic enhancement of photocatalytic activity of the photostructured visible active NdT/OP catalysts,compared to NdT catalyst,was observed. Only CO2 was detected in gas-phase during visible light irradiation,proving that the photocatalytic process is effective in the mineralization of spiramycin,reaching very high values of TOC removal. The photocatalyst NdT/OP at 30 wt.% of NdT loading showed the highest photocatalytic activity（58%of TOC removed after 180 min irradiation against only 31% removal after 300 min of irradiation of NdT）. We attribute this enhanced activity to the high effectiveness in the utilization of visible light through improved light harvesting and exploiting. OP particles act as ＂photoactive support＂,able to be excited by the external visible light irradiation,and reissue luminescence of wavelength suitable to promote NdT photomineralization activity.

关键词： Photocatalysis Visible light N-doped TiO2 Up-conversion phosphors Spiramycin mineralization